Asyncio and MIDI

clicktrack.py

import asyncio
import board
import time
import usb_midi
import adafruit_midi
from adafruit_midi.note_on import NoteOn
from adafruit_midi.note_off import NoteOff
from neopixel import NeoPixel
from adafruit_seesaw.seesaw import Seesaw
from adafruit_seesaw.analoginput import AnalogInput

def bpm_to_t(rate):
    return 60/rate/4.0

class Ticker:
    def __init__(self):
        self.bpm = 20
        self.tick = bpm_to_t(self.bpm)
        self.note = 38
        self.running = True
        self.tock = 0

async def loop(ticker):
    midi = adafruit_midi.MIDI(midi_in=usb_midi.ports[0],
        midi_out=usb_midi.ports[1],
        in_channel=1,
        out_channel=1)
    while ticker.running:
        note = ticker.note
        midi.send(NoteOn(ticker.note, 120))
        await asyncio.sleep(ticker.tick)
        midi.send(NoteOn(note, 30))
        await asyncio.sleep(ticker.tick)
        midi.send(NoteOn(note, 30))
        await asyncio.sleep(ticker.tick)
        midi.send(NoteOff(note, 0))
        
async def read_ain(ticker):
    seesaw = Seesaw(board.I2C())
    a7 = AnalogInput(seesaw, 7)
    while True:
        raw = a7.value
        ticker.bpm = int(raw/1023*120)+20
        ticker.tick = bpm_to_t(ticker.bpm)
        await asyncio.sleep(0.1)

async def main():
    ticker = Ticker()
    await asyncio.gather(
        loop(ticker),
        read_ain(ticker)
    )
asyncio.run(main())